Patents by Inventor Tetsuo Ueyama

Tetsuo Ueyama has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5085496
    Abstract: An optical element comprises a polarization diffraction element that is provided with diffraction gratings that are respectively mounted on different faces of a transparent substrate of a flat plate shape, which grating pitches are equal to each other and approximately equal to the wavelength of an incident light, and which grating lines are parallel. The thickness of the substrate is set such that the difference that occurs between the phases of the P and S polarizations of a light due to the grating, and the difference that occurs between the phases of the two polarizations when the light propagates through the substrate cancel out.
    Type: Grant
    Filed: March 28, 1990
    Date of Patent: February 4, 1992
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yoshio Yoshida, Takahiro Miyake, Yasuo Nakata, Yukio Kurata, Nobuo Ogata, Tetsuo Ueyama, Hideaki Sato